summaryrefslogtreecommitdiff
path: root/include/linux/rtc
diff options
context:
space:
mode:
authorKeerthy <j-keerthy@ti.com>2019-04-03 10:27:39 +0530
committerTony Lindgren <tony@atomide.com>2019-04-08 10:22:12 -0700
commit6256f7f7f217b2216fcb73929508325f4ee98237 (patch)
tree933876dca6be2a54dc5ef389258bf50c8b736615 /include/linux/rtc
parent9e98c678c2d6ae3a17cb2de55d17f69dddaa231b (diff)
rtc: OMAP: Add support for rtc-only mode
Prepare rtc driver for rtc-only with DDR in self-refresh mode. omap_rtc_power_off now should cater to two features: 1) RTC plus DDR in self-refresh is power a saving mode where in the entire system including the different voltage rails from PMIC are shutdown except the ones feeding on to RTC and DDR. DDR is kept in self-refresh hence the contents are preserved. RTC ALARM2 is connected to PMIC_EN line once we the ALARM2 is triggered we enter the mode with DDR in self-refresh and RTC Ticking. After a predetermined time an RTC ALARM1 triggers waking up the system[1]. The control goes to bootloader. The bootloader then checks RTC scratchpad registers to confirm it was an rtc_only wakeup and follows a different path, configure bare minimal clocks for ddr and then jumps to the resume address in another RTC scratchpad registers and transfers the control to Kernel. Kernel then restores the saved context. omap_rtc_power_off_program does the ALARM2 programming part. [1] http://www.ti.com/lit/ug/spruhl7h/spruhl7h.pdf Page 2884 2) Power-off: This is usual poweroff mode. omap_rtc_power_off calls the above omap_rtc_power_off_program function and in addition to that programs the OMAP_RTC_PMIC_REG for any external wake ups for PMIC like the pushbutton and shuts off the PMIC. Hence the split in omap_rtc_power_off. Signed-off-by: Keerthy <j-keerthy@ti.com> Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> [tony@atomide.com: folded in a fix for compile warning] Signed-off-by: Tony Lindgren <tony@atomide.com>
Diffstat (limited to 'include/linux/rtc')
-rw-r--r--include/linux/rtc/rtc-omap.h7
1 files changed, 7 insertions, 0 deletions
diff --git a/include/linux/rtc/rtc-omap.h b/include/linux/rtc/rtc-omap.h
new file mode 100644
index 000000000000..9f03a329e63f
--- /dev/null
+++ b/include/linux/rtc/rtc-omap.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _LINUX_RTCOMAP_H_
+#define _LINUX_RTCOMAP_H_
+
+int omap_rtc_power_off_program(struct device *dev);
+#endif /* _LINUX_RTCOMAP_H_ */